In other words, how your thyroid responds to your supplementation program will always be the limiting factor, even if iodine in mega dosages can cure cancer. Prevention is always better than cure. Remember that the iodine story is about meeting your iodine needs from a healthy diet. Mankind evolved eating relatively low levels of iodine, after all. While mega-dose iodine therapy might be able to cure both prostate and breast cancer, the likely outcome would be serious damage to and even the destruction of your thyroid glands, which should never be viewed as being desirable.
The maximum cancer preventative dosage, for someone deficient in iodine would be 480 mcg or in the thyroid safe range of 330 to 500 mcg per day which is calculated from what Japanese women consumed of seaweed, using correctly its dry weight.[Nagataki 1967]
Is Iodine Supplementation Advisable
Whether or not you should supplement with iodine depends on a number of different factors. Mainly it is about what kind of public health salt iodization program your country of residence has. Find out, now, where your country stands on the latest status of their salt iodization program, by clicking on this link. Of course, it also depends upon whether or not you are actively avoiding the use of iodized salt. Further, whether or not you regularly eat seafood or seaweed, also, factors in.
A few countries with too aggressive an iodization program are producing people who are suffering from hyperthyroidism. Clearly, people who live in these countries should cut back on their use of iodized salt and not supplement with iodine. In addition, they might benefit from selenium supplementation.[Triggiani 2009]
Iodine supplementation therapy mathematically exhibits a very tight U-curve shaped effect, where consuming too much iodine is just as bad if not worst than too little. Excess iodine can induce hyperthyroidism (Jod-Basedow phenomenon) or autoimmune thyroiditis, such as Hashimoto’s disease.
Avoid Iodine Supplementation In Hashimoto's
The Recommended Daily Allowance for Iodine
The American RDA for iodine is 150 mcg. Iodine supplementation for expecting mothers is an easy way to boost the I.Q. of their babies. During pregnancy iodine intake should be raised to 220 mcg, and 270 mcg while breastfeeding. The upper safe limit for iodine is 1,100 mcg or 1.1 mg per day. The World Health Organization (WHO) has provided a formula for calculating maximal tolerable daily intake at 17 mcg/kg or 2.2 pounds of body weight. For people weighing 150 pounds, 68 kilograms, or 11 stone that works out to 1.16 mg or 1,160 mcg per day. [Sang 2012], [Patrick 2008]
Iodine Cofactors
There are a few other nutrients that are utilized by iodine.
"Selenium deficiency can exacerbate the effects of iodine deficiency and the same is true for vitamin A or iron deficiency."[Triggiani 2009]
Blood Tests for Thyroid Disorders
Health research studies on adequate iodine nutrition generally test for urinary iodine.
| Urinary Iodine (mcg/L) |
Iodine Intake | Iodine Status |
| < 99 | Insufficient | Iodine Deficiency |
| 100 – 199 | Adequate | Optimal Urinary Levels of Iodine |
| 200 – 299 | Borderline Excessive | Some risk of hyperthyroidism |
| ≥ 300 | Excessive | Clear danger of iodine-induced hyperthyroidism or autoimmune thyroiditis |
Rather than take a spot or 24 hour load test, what your really need to do is take blood tests that monitor TSH, T4, and T3 blood levels. The Thyroid Cascade Profile that tests for TSH and TPO antibodies is a good test for Hashimoto's thyroiditis. Physicians rarely do urine tests for urinary iodine levels in America.
The best way to supplement with iodine is to go slow.
Supplementing with high dosage iodine, or 1 mg or more per day, is fraught with risks.[Hoang 2013] The Natural Health Perspective advises against people taking any over-the-counter high dosage preparation of iodine. Those suffering from Hashimoto's thyroiditis react very negatively to high dosage iodine supplementation.
There is. also, reason to believe that moving too fast from a state of iodine deficiency to one of excessive intake is more destructive to your health than mere measurements of absolute urinary iodine levels. Indeed, sudden dramatic increases in iodine supplementation can result in hyperthyroidism or autoimmune Hashimoto's thyroiditis.[Andersson 2012]
"Dietary iodide intakes of 750 micrograms/day or more may adversely affect thyroid function, especially in individuals with borderline hypothyroidism."[Chow 1991]
In conclusion, the Natural Health Perspective advocates that it is better to start slow and simply wait for the iodine to start accumulating in your body. Try to supplement with a couple hundred mcg rather than in the mg dosage range.
Please read our Nutritional Supplements Disclaimer.
References
- Role of iodine, selenium and other micronutrients in thyroid function and disorders.
Triggiani V, Tafaro E, Giagulli VA, ...
Endocr Metab Immune Disord Drug Targets. 2009 Sep;9(3):277-94. Epub 2009 Sep 1. Review.
PMID: 19594417 - Global iodine status in 2011 and trends over the past decade.
Andersson M, Karumbunathan V, Zimmermann MB.
J Nutr. 2012 Apr;142(4):744-50. doi: 10.3945/jn.111.149393. Epub 2012 Feb 29. Erratum in: J Nutr. 2012 Jun;142(6):1128.
PMID: 22378324 - Exploration of the safe upper level of iodine intake in euthyroid Chinese adults: a randomized double-blind trial.
Sang Z, Wang PP, Yao Z, ...
Am J Clin Nutr. 2012 Feb;95(2):367-73. doi: 10.3945/ajcn.111.028001. Epub 2011 Dec 28.
PMID: 2220531 - Iodine: deficiency and therapeutic considerations.
Patrick L.
Altern Med Rev. 2008 Jun;13(2):116-27. Review.
PMID: 18590348 - Over-the-counter-drug-induced thyroid disorders.
Hoang TD, Mai VQ, Clyde PW, ...
Endocr Pract. 2013 Mar-Apr;19(2):268-74. doi: 10.4158/EP12298.OR.
PMID: 23529350 - Iodine deficiency.
Zimmermann MB.
Endocr Rev. 2009 Jun;30(4):376-408. doi: 10.1210/er.2009-0011. Epub 2009 May 21. Review.
PMID: 19460960 - Effect of low dose iodide supplementation on thyroid function in potentially susceptible subjects: are dietary iodide levels in Britain acceptable?
Chow CC, Phillips DI, Lazarus JH, ...
Clin Endocrinol (Oxf). 1991 May;34(5):413-6.
PMID: 2060151 - Thyroid function in chronic excess iodide ingestion: comparison of thyroidal absolute iodine uptake and degradation of thyroxine in euthyroid Japanese subjects.
Nagataki S, Shizume K, Nakao K.
J Clin Endocrinol Metab. 1967 May;27(5):638-47.
PMID: 4164900 - Iodine in evolution of salivary glands and in oral health.
Venturi S, Venturi M.
Nutr Health. 2009;20(2):119-34. Review.
PMID: 19835108 - Miller, D.W. (2006). Extrathyroidal Benefits of Iodine. J Am Phys and Surg., 11(4), 106-110.
